The purpose of the experiment is to investigate if changes in temperature affect the reaction rates of the potato enzyme, catechol oxidase. The enzymatic activity will be measured at three different temperatures with a spectrophotometer. The results will indicate the optimal temperate conditions for enzyme-catalyzed reactions.
Introduction
Living organisms are maintained by a complex system of biochemical reactions. Nearly all of these reactions require the assistance of enzymes. Enzymes are proteins that are capable of speeding up specific chemical reactions by lowering the amount of energy needed to start the reaction. A substrate is necessary to activate an enzyme, and does so by attaching itself to a specific site on the enzyme.
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Understanding this process and how temperature impacts enzymatic reaction rates are necessary for farmers and the food industry. Optimal storage for the potato will be at a temperature that allows the least amount of enzymatic activity. This can extend the time that potatoes can be stored for future use (Hyde). The purpose of the experiment is to measure the enzymatic activity at different temperatures. These temperatures will be: 0°C, 40°C, and 60°C. Enzymes typically preform the best at body temperature, or 37°C. Raising that temperature can increase the activity rate. If the temperature is too high, it can cause the enzyme to denature and not work. The enzymatic reactions were measured with a spectrophotometer. The instrument evaluates the amount of light a solution can absorb. The more opaque a solution is, the more light it can absorb. The absorption rates directly correlate with enzymatic activity, indicating that high absorption rates indicate high enzymatic activity. If the absorption rate is low, then the enzyme is failing to bind to the
Catechol, in the presence of oxygen is oxidized by catechol oxidase to form benzoquinone (Harel et al., 1964). Bananas and potatoes contain catechol oxidase that acts on catechol which is initially colorless and converts it to brown (Harel et al., 1964). In this experiment, the effect of pH on the activity of catechol oxidase was conducted using buffers ranging from pH2 to pH10. Two trials were conducted due to the first trial results being altered by an external factor. The results were acquired by taking readings every 2 minutes for 20 minutes from a spectrophotometer and then recorded on to the table. The data collected in the table were then made into graphs to illustrate the influence of pH on the catechol oxidase catalyzed reaction. After analysis, the data revealed that pH did have a significant influence on the enzyme as recorded by absorbance per minute. However, the data was collected was not accurate due to external factors, thus the results are debatable and should be experimented again for validation.
The role of an enzyme is to catalyse reactions within a cell. The enzyme present in a potato (Solanum Tuberosum) is catechol oxidase. In this experiment, the enzyme activity was tested under different temperature and pH conditions. The objective of this experiment was to determine the ideal conditions under which catechol oxidase catalyses reactions. In order to do this, catechol was catalyzed by catechol oxidase into benzoquinone at diverse temperatures and pH values. The enzyme was exposed to its new environment for 5 minutes before the absorbance of the catechol oxidase was measured at 420 nm using a spectrophotometer. The use of a spectrophotometer was crucial for the collection of data in this experiment. When exposed to hot and cold temperatures, some enzymes were found to denature causing the activity to decrease. Similarly, when the pH was too high or low, then the catechol oxidase enzyme experienced a significant decrease in activity. It can be concluded after completing this experiment that the optimal pH for catechol oxidase is 7 and that the prime temperature is 20º C. Due to the fact that the catechol oxidase was only tested under several different temperatures and pH values, it is always possible to get a more precise result by decreasing the increments between the test values. However, our experiment was able to produce accurate results as to the
After the substrate solution was added, five drops of the enzyme were quickly placed in tubes 3, 4 and 5. There were no drops of enzyme added in tubes 1 and 2 and in tube 6 ten drops were added. Once the enzyme solution has been added the tubes were then left to incubate for ten minutes and after five drops of DNSA solution were added to tubes 1 to 6. The tubes were then placed in a hot block at 80-90oC for five minutes. They were then taken out after the five minute period and using a 5 ml pipette, 5 ml of distilled water were added to the 6 tubes and mixed by inversion. Once everything was complete the 6 tubes were then taken to the Milton Roy Company Spectronic 21 and the absorbance of each tube was tested.
The products produced by the first reaction were used as a substrate for the second. In this case the enzyme used NADH, which resulted in the decreased absorbance due to the NADH oxidation to NAD+. In addition, the spectrophotometer was used as a measuring device to follow the change in absorbance of the NADH molecules at 340nm.
We then tested the last set of test tubes containing milk and lactase, we did this to find which ones would present the most glucose concentration results, when placed in different temperatures, 4°C, boiling and room temperature. What we wanted to know was how far temperature could affect lactase to perform its enzymatic activity. We hypothesized that if the lactase is placed in a high or low temperature outside its active range, the temperatures would have a negative impact on the functions of the enzyme. If the temperature has an affect on lactose then we would see some temperatures in which lactase will be function able. We came to a conclusion that enzymes work at a temperature that is closest to body temperature (25°C); boiling water (100°C) denatures the enzyme, while the enzyme is not able to function properly if
In the exercise # 2 we observed the effect of substrate concentration, enzyme concentration, pH and temperature on enzyme activity. All the data showed that once potato extract was added to catechol and water the reaction varied dependent on the level of catechol. As in
Temperature controls the speed the enzymes work at. Higher temperatures increase the kinetic energy which increases the chance of collision therefore speeding up the rate of
The purpose of this experiment was to record catalase enzyme activity with different temperatures and substrate concentrations. It was hypothesized that, until all active sites were bound, as the substrate concentration increased, the reaction rate would increase. The first experiment consisted of five different substrate concentrations, 0.8%, 0.4%, 0.2%, 0.1%, and 0% H2O2. The second experiment was completed using 0.8% substrate concentration and four different temperatures of enzymes ranging from cold to boiled. It was hypothesized that as the temperature increased, the reaction rate would increase. This would occur until the enzyme was denatured. The results from the two experiments show that the more substrate concentration,
With the desire of wanting to know how to increase the enzyme’s activity rate, the experimenters formulate a question that is which temperature will cause the potato enzyme to decompose the most hydrogen peroxide? In order to find the answer to this inquiry, experimenters started the procedure by preparing four different potato samples, where there were, hot, cold, room temperature, and baked potato samples. Each sample was half of two Idaho potato, which was cut into fourths. Then, each group of potatoes were examined when each section was submerged in 150 mL of hydrogen peroxide in individual beakers. The results were recorded based on the physical appearances of each reaction.
Introduction: Starting out with some background information, I know that enzymes are biological catalysts. The enzyme that I used for this experiment was potato juice. Enzymes make reaction rates go faster. They lower activation energy, making chemical reactions. Temperature has an effect on canola cultivars. The higher temperature decreased stem diameter, but room temperature had thicker stems. So I believe the same will happen for the catechol oxidase; the solution will react faster at room temperature. Other enzymes can also have different effects such as the enzyme in cattle serum. The enzyme lost activity in room temperature. With that being said room temperature can also be detrimental with specific enzymes. Fungus also
Enzymes are soluble protein molecules that are fundamental in the maintenance of biological functioning. Their primary purpose is to take on the form of a catalyst during chemical reactions in order to lower the activation energy levels required during the reaction and therefore, change the rate at which equilibrium occurs. Each enzyme is highly selective which means they will only act on specific substrates in particular reactions to convert them to products with different molecular structures.
Enzymes are proteins that work as biological catalysts. Enzymes work by increasing the rate chemical reactions that are taking place within living cells. Enzymes are particular to what they will catalyze and are reusable. Enzymes have a specifically shaped area called an active site. An active site is a restricted region of an enzyme molecule which binds the substrate.
Enzymes are biological molecule that speed up biochemical reactions within an organism. Enzymes are found in all living organism because the perform vital functions for the body such as digestion and metabolism. Substrate are reactant in an enzyme-catalysed reaction upon which the substrate is bonded to the active site. The active site is where the substrate molecules bind to so that the enzyme can convert the substrate into different molecules known as products. The shape of an enzyme allows it to only bind to a specific substrate like a lock and key method analogy.
Biology 121 KS Lab Report IV 03/06/2018 Jannet Marin Testing the Effects of Temperature and pH on Potato Catalase Activity Introduction: To bear life in the cell, nearly all metabolic processes need enzymes. Enzymes are “macromolecular biological catalysts that help to speed up, or catalyze, chemical reactions.” The activity of enzymes is also affected by changes in the pH and temperatures. However, tremendously high or low pH and temperature values could cause complete loss of activity for most enzymes. Catalase is the most common enzyme found in potatoes and almost all organisms that are exposed to oxygen.
This lab tested the effectiveness of the catalase enzyme, against hydrogen peroxide, in varying temperature conditions. The hydrogen peroxide was heated or cooled to 5 different temperatures: the first sample was cooled to 8° to test the rate of reaction in cold temperatures, the next sample was heated to 30° to resemble human body temperature which is 37° (HealthLinkBC, 2016), the third and fourth samples were set to 50° and 70°, respectively, to measure the effects heat on the enzymes, the last sample was left at room temperature, 24°, and used as a control. According to enzyme theory, as the temperature of a reaction increases, the amount of energy within a system increases, allowing reactions to occur more readily, and at a faster rate